The present invention relates to a tail rotor system, and more particularly to the replacement of a tail rotor pitch horn which minimizes disturbance of the preexisting tail rotor blade structure.
Conventional tail rotor systems are provided in a variety of different specific constructions. A cross-beam tail rotor blade system accommodates blade flap and pitch change motion by deflection of a flexible graphite fiber spar. The spar is a continuous member running from a tip of one tail rotor blade to a tip of the opposite tail rotor blade. Pitch control horns mounted to the inboard section of each tail rotor blade are driven by actuators to deflect the tail rotor blades and flex the spar to provide a desired anti-torque action in response to pilot inputs. The pitch control horns are manufactured as one-piece cuffs which receive the spar therethrough and attach to the blade skins which are mounted thereafter.
During assembly of such tail rotor systems, the pitch control horns are slid longitudinally over the spar toward the center thereof prior to bonding of the core and blade skins to longitudinal outboard section of the spar. After mounting of the core and blade skins to the spar, the pitch control horns are bonded into the inboard section of the blade skins to communicate the pitch force from an actuator to the tail rotor blades and to seal the inboard open end of the blade skins. A strong, effective and lightweight tail rotor system is thereby provided which minimizes the necessity of lubrication and bearings.
Disadvantageously, due to the above described manufacturing method, when damage/corrosion beyond predetermined limits occurs to one pitch control horn, the entire tail rotor system must be replaced. Replacement of the entire tail rotor system is relatively expensive.
Accordingly, it is desirable to provide a repair method to replace the pitch control horns while minimizing disturbance of the preexisting tail rotor blade structure.